Vacuum means for conserving lubricating oil of internal-combustion engines



v 1,6182861 c. s. CLARK VACUUK MEANS FOR CONSERVING LUBRICATING OIL 0FINTRNAL COMBUSTION ENGINES Filed uw. 11. 192s 2 Sheets-sheen Feb. 22,1927.

mlmuHH .HIHIIIHIIIIIIII Feb. 2z, 1927. v 1518,861

c. s. CLARK VACUUM'MEANS FOR CGNSERVING LUBRICATING OIL 0F INTERNALCOMBUSTION ENGINES Filed Dec. 11. l192s 2 sheets-sheets x. Q n 35%Patented Feb. 22, 1927.

UNITED STATES f 1,618,861'` PATENT OFFICE.

CORNELIUS S. CLARK, OF NORFOLK, VIRGINIA, ASSIGNOR TO CLARK ENGINEERINGCORPORATION, OF,NORFOLK, VIRGINIA, A CORPGRA'IIONl OF VIRGINIA.

VACUUM .MEANS FOR' CONSERVING LUBRICATING OIL OYFV`INTERNAL-COMBUSTION lf lENGINES.

Application filed Deceniber.1l,'1923. Serial No. 680,031.

This invention relates to vacuum meansv for conserving the lubricatingoil of internal combustion engines, and has for its main object anarrangement of structure bymeans of which Vthe surplus oil passingfromthe crank case to the combustion chamber. `between the cylinder andpiston, andthe nonvolatile fuel fraction passing by vthe same route fromthe combustion chamber to the crank case, are withdrawn byv suction, and

delivered tov the intake of theV engine to f form a part of thecombustible mixture. By

this means, not onlyis the incrustation off' charred oil on the walls ofthe combustion chamber prevented, but dilution of the crank case oilisavoided, preserving the viscosity and lubricating properties of theoil.-

`Another object v,of the' invention` vis the novel piston and'cylinderconstruction which makes possible the withdrawal: of the surplussubstances in the manner-set forth.

For the attainmentfof these ends and the accomplishment of other newandA useful objects,` as will appear, the invention con-l slsts in thefea-tures of novelty-inzthe con-J struction, combination and arrangementof the several parts generally shown in the' accompanying drawings l and.described in the specification, butv more `particularly pointed outinther appended claim. ln the drawings Fioure lis a side elevation of amulti- D Y cylinder internal combustion engine, illustrating theinvention, two of thev cylinders being shown in'section. y I I Figure 2yis an. elevation, in section, of a single cylinder showingia modifiedform of the invention with therpiston at the top of its stroke. t i yFigure 3 a similar-view,partsbeing broken away, the pistgnbeingshownatvthe bottom of its stroke. v

Figure 4 is a cross. section taken along the line 4 4: of Figure 3. f

Referring now in detail to the severalV iigures, the numeral lrepresents the cylinder block of a multi-cylinder internal combustionengine, the intake manifold of' which is represented at 2. For thepurpose of carrying out my invention, the walls of eacli of thecylinders are formed with an annular groove 3 adjacent' the lower limitof the range of travel of the piston. Each of these grooves is incommunicationr with a conduit'4,-said conduits being 'branches of a willbecommunicated to the annular grooves 3.. In each ofthe modificationsshown theY pistons must be of such length relative toi the strokethereof, that the grooves 3 are constantly within the range of travel ofsaid pistons. Otherwise, were thetop of the pistons to descend` belowthe annular grooves, ory were the'- lower ends of said 'pistonslto riseabove said grooves the vacuum in themanifold 2 would be'filled'* byatmosphere from either the combustion` chamberorv crank case,interrupting thel functioning of* the carburet'er.

In the form ofthe invention shown in` Figurehthe piston is provided atits top.`

with a single ring groove 7-which may carry a sealing ring f8 of anyapproved type, rbut preferablywa Y composite ring, also consti,- tutingmyvinvention and claimed and described in a companion application forPatent No; 680,032. The skirt 9'of'this piston is without aringgrooveat' the bottom, so

that. the sealing effect is ymostly at the top,` Y andthe vacuum oilconserving system lmay be expected to draw a considerable proportion ofthecrank casevapor into the intake manifold along with the surplusoilorliquid iso I.

fuel that may find its way between the pisy vton and cylinder. y Theintroduction of such*` yapor into the. intake manifold is notyobjectionable, as it consists largely of morev or less volatilecombustible gas andadds to the richness of the mixturekfedtothe engine,

toV compensate for 4which a leaner adjustment of thelcarbureter (notshown) may-be made rlfhis'fo'rm of ipistonihas the yadvantage that,providing Vthe skirt is long enough to cover the annular groove 3 whenthe piston is at its upper dead center, any of the ordinary forms ofplain skirt piston may be adapted to use with the oil conserving sys'-tem Without material change. It is essential that the piston ring v8does not pass across the annular groove 3,' orit may spread linto Vsaidgroove and lock the piston againstfurther movement. ever, that thepiston ring'S yshould descend It vis preferable, howioo slightly belowthe upper-edge vof the groove 3 as shown at 10 in Figure 1 to avoid thewearing, of a ridge in the cylinder wall at a point where the pistonring stops. The action of the piston ring is that of scraping the oil-down the side of the cylinder into the annular groove 3 whence it iscarried into the intake manifold by suction.

In Figures 2 and 3 is shown a modilied forni of the invention in whichthe annular groove is omitted from the cylinder wall, the oil-collectinggroove being formed upon the piston Vbody below the upper piston ring.rllhis groove may be of any desired forni but is preferably shown as aspiral 11 encircling the piston several times so as to cover a zone aswide as approximately one-third of the piston stroke. By this means,the-oilcollecting groove 11 comes into registry with the nipple 12 whenthe piston has travelled two-thirds its distance on the sucthe intakemanifold, upon the joint between Y the cylinder and piston is relativelyinactive so that lubrication of the piston is not in- But as the pistondescends the intake valve the pumping oi oil past the istonring and intothe combustion chamber ecomes acute. It is at this tima-just before theopening of the intake valve 1 5, and continuing to the end of thedownward stroke of the piston that the nipple 12 is in oomi'nunicationwith the spiral groove 11, the saine suction which prevails in thecombustion chamber being applied to the spiral groove through the nipple12, counter-acting the pumping action of the combustion chamber landwithdrawing the surplus oil trom'the spiral groove vinto they intakeinaniold 2. For the purpose ot ensuring proper lubrication of thereciprocating parts it is advisable to segregate the piston ring groove7. from the spiral groove 11, to which end I have provided that thespiral groove shall terminate in a circular portion 13 just ybelow thepiston ring groove 7 'but out of communication therewith.

In the form of the invention shown in Figures 2 and 3 the pistons areeach provided with a piston ring 14 at the lower der be made suilicientto prevent the spiead- Y ing of the ring into the crank case chamberbelow the endof the cylinder.

It will be understood that wherever the term oil is used throughout thespecification and. claim it is intended to cover not only the` surpluslubricating oil which may be pumped up from the crank case between theIcylinder piston walls but also the less volatile portion oi the fuelmixture which may condense within.` the combustion chamber during thecompression and explosion strokes ot the engine, and which; if permittedto mix with the crank case oil would soon destroy Y the lubricatingproperties of the same;V y

I consider that my invention, resides primarily in the broad aspectshereinbetore set forth, and only secondarily inthe details ofconstruction` and arrangement, wherefore I do not restrict myseltl tothe particular construction here disclosed, but only by the,

terms of the claim and the stateofV the prior art. j j g Havingdescribed my invention what I claim as new andl desire .to secure by;Letters Patent, is

i In an internal combustion engine, a, cylinder, a piston'reciprocabletherein, theewall ot sa'id cylinder being provided; with aport adjacentthe lower limit otv the range oi: travel of said piston, meansestablishing communication between said port and the combustible mixtureintake of; saidengine. a piston ring adjacent the upper end ot'Isaidpiston and an oil collecting groove arfy ranged around said pistonbelow said piston ring and covering a Vzone of such width as to bringthe. lower portion of said Ioil collecting groove into registry `withsaid; port substantially at the time of opening'ot the inlet` valveengine.

1n; testimony whereofV l lhave Yhereuntov setf Vniy hand.

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